Thrips and whitefly

[Marb67]

Every year its the same. £#&*@£”% thrips chewing up many plant and veg leaves causing them to be sickly and distroted for the rest of the season, as well as whitefly in the base of compost, causing young plants I have carefuly nutured from seed to die off. They are outside and in the greenhouse. I have tried soapy water and garlic spray to no avail. I just give up as I do not want to use chemicals.

Anyone else cursed with these and many other pests that make it almost not worth bothering with ?

[Scarlet]

Do you clean out your GH every year Marb?

[SarrissUK]

I've used some of the advice on this page, particularly the neem oil and thoroughly cleaning out the greenhouse every year, and making sure no greens are left on the ground anywhere.
https://www.planetnatural.com/pest-p...hrips-control/

[SarrissUK]

Personally, if I've tried everything else, I have no quarms about using chemicals. The very small amount that I use, is far less than I'd get in commercially grown crops.

[Marb67]

Yes, I clean my greenhouse but they come from outside.

[Marb67]

So why when I soak the whitefly and small aphids in soapy water does it fail to kill them ? Little gits are still there killing my young seedlings.

[Runtpuppy]

Oh, Marb, I think you'll find this very satisfying. Yesterday evening, when I was busy procrastinating and avoiding the work I was supposed to do, I went into the blowaway to stare at my tomato and chilli plants. The bigger chilli plant had some aphids that I have been regularly squashing. Yesterday, I saw a hoverfly larva there. I looked a bit more closely and there were a lot of really tiny ones as well.

But I needed to be sure, so I used a stalk of grass to transfer an aphid each in front of two of them. Watched their little mouth ends go into hyperdrive, grab the green vampires, and munch on them happily.

I felt so evil, and yet... so satisfied!

[Marb67]

For the life of me I just don.’t know where they come from. I carefuly lifted the seedlings from the infected post. Washed them all off and squashed others. Re-planted in clean compost, clean pot and left in kitchen window. Next morning more aphids. So where did they come from ?

[Runtpuppy]

According to this, they are wingless but develop wings when overcrowded. In that case, the compost doesn't matter. They'll just land on the plants they like when they go a-flying.

https://www.rhs.org.uk/advice/profile?PID=181

[Penellype]

For the life of me I just don.’t know where they come from. I carefuly lifted the seedlings from the infected post. Washed them all off and squashed others. Re-planted in clean compost, clean pot and left in kitchen window. Next morning more aphids. So where did they come from ?

Young aphids are very small, and as they are born pregnant you only need to miss one and they are back in no time at all. I've had them on a pepper plant in the house and despite going over every inch of the plant several times a day, I eventually had to admit defeat and put it outside.

[Marb67]

What about thrips, they are impossible to get rid of. Tiny lime green thin jumping things. All the top new leaves of plants are distorting because of their tiny holes. I have squashed any I see but it’s depressing to think I am cursed with them for all the time I am here

[Runtpuppy]

The 2-3 websites I read after searching for thrips seem to agree that non-chemical methods include introducing predatory mites or using blue sticky tape.

https://www.rhs.org.uk/advice/profile?PID=876

This one says ladybugs and lacewings also help.

https://www.planetnatural.com/pest-p...hrips-control/

I don't think you'd ever be able to kill them off completely unless you use severe chemical methods. However, if you can reduce their numbers, you won't get as much damage.

That's what I generally aim for. I don't like killing things off completely because that would disbalance the ecosystem in my garden. So I aim to keep them under control just enough so I can get something to eat myself.

If it's things I am cooking, I don't even bother about removing damaged bits. Just wash them well and the heat will take care of the rest. The chard I've been harvesting, I am lucky to get 2-3 leaves out of 10 without any slug-damage. I let myself feel happy about those and just wash the rest well before cooking. They're gonna wilt down anyway.